Tokyo: Former world number one Caroline Wozniacki issued a stark warning she was back to her best Wednesday as she ousted China's former French Open champion Li Na to reach the Pan Pacific Open quarter-finals in Tokyo.
Wozniacki ground out a 4-6, 6-3, 6-4 win to join a powerful last eight, where she will play defending champion Agnieszka Radwanska. Maria Sharapova, Samantha Stosur and world number one Victoria Azarenka are also through.
Denmark's Wozniacki won her first WTA title in more than a year last week in Seoul, and she was not to be denied despite going a set down against Li. Showing trademark grit, she toughed it out in the last set for her eighth straight win.